Press, particularly intended for compression of bark



DeC- 1967 K. K. HALMEKYTO 3,356,015

PRESS, PARTICULARLY INTENDED FOR COMPRESSION OF BARK Filed July 7, 1965 2 Sheets-Sheet 1 Dec. 5, 1967 K. K. HALMEKYTO 3,356,015 I PRESS, PARTICULARLY INTENDED FOR COMPRESSION OF BARK Filed July 7, 1965 2 Sheets-Sheet 2 FIG.4

GOOD FIG.5

FIG.6

/ IN VEN TOR.

///1/4 P15 /K HA1 Mf/f/TO KLALYAY/LYA V4 V] V United States Patent 3,356,015 PRESS, PARTICULARLY INTENDED FUR COMPRESSION 0F BARK Kaarlo K. Halmekyto, Vanha Kapyla, Helsinki, Finland,

assignor to 0y Tampella Ab, Tampere, Finland, a corporation of Finland Filed July 7, 1965, Ser. No. 470,071 Claims priority, application Finland, July 10, 1964, 1,480/64 8 Claims. (Cl. 100-95) The invention concerns a press, particularly intended for compression of and water removal from bark, etc. The press covered by the invention is especially suited for compression of bark waste received in cellulose mills into a shape and dryness suitable to be burned.

Before the present invention, presses of this type based on pistons, rollers, the screw principle have been known; the common drawback encountered with them consisted of feed problems. For instance, in presses employing rollers or chain mats the material to be compressed tends to collect in front of a relatively small and unchanged compression point, and this greatly hampers the feeding of the material through the press. The piston must, in presses of this type, perform an idling return movement in between the compression strokes, and this markedly reduces the capacity of the press. Presses employing screws carry space requiring pressing equipment within the pressing space.

An object of the press in accordance with the present invention is to remove the above mentioned drawbacks, and it is a main characteristic of a press conforming with the invention that it comprises two feed spaces intended for bark feeding which together form two interconnected press chambers, a piston moving back and forth through the feed space and pushing in turn both press chambers as well as a press member, being in turn pushed in a synchronized manner together with the piston. The piston is installed in such manner as to feed a bark portion from the feed space in turn into both press chambers to be compressed by the mentioned press member.

In accordance with the invention, it is possible to make an effective, double-acting, bark press of very simple design. Because the piston produces a feeding stage in both directions of movement, no idling becomes involved in the piston movement. Because the press member is only pushed into the press chamber during the compression stage, and it is essentially removed during the bark feeding stage, an unobstructed feeding of bark portions into the press chamber is afforded. A structure conforming with the invention makes use of the piston as a counter plate during the bark compression in addition to its function as a feeding member, and makes it possible to reach high compression ratios with the press. The invention provides also permits the use of ordinary hydraulic equipment to synchronize the movements of the press member and the piston. As the invention provides a common feeding piston for both compression chambers, a very big capacity is received with a relatively compact press. The invention is further explained with reference to the enclosed drawing, which shows a screw press of advantageous shape conforming with the invention.

FIG. 1 shows the press partially in vertical section and partially in side elevation.

FIG. 2 is a fragmentary view in bottom plan.

FIG. 3 is an enlarged vertical section along line 3-3 in FIG. 2.

FIG. 4 is a fragmentary view in vertical longitudinal section through the right-hand arm of the press lever,

the section being taken generally along the line 44 of FIG. 1.

FIG. 5 is a fragmentary View in vertical longitudinal section through the press showing the feed piston in elevation, the section being taken generally along the line 5-5 of FIG. 1.

FIG. 6 is a view in transverse vertical section through the arm 13 of the apparatus, the section being taken along the line 66 of FIG. 1 looking in the direction of the arrows.

The bark press shown in the drawing has a sturdy foundation plate 1, and on this are two separate spaced parallel walls 2 and 3, the vertical transverse section of which form together with the foundation plate a rectangular, essentially horizontal chute which is open upwards and at the ends. Above the center of the chute there is disposed a feed hopper 4 for conveying the bark to be compressed to the feed space 5 underneath of the chute. The chute parts located on both sides of the feeding hopper form two compression chambers 6 and 7 .which, as shown, are located on the same axis in respect of each other, and are connected by the central feed space. The side walls of the compression chambers are perforated as shown at 8. The water that escapes outwardly through the holes 8 in the side walls of the chambers of the press is led away through drain passages (not shown) in the base of the press.

At the side walls of the chute and above it are upwardly projecting brackets 9 fastened to the foundation plate on both sides of the feeding hopper. An elongated hollow press lever 11 is pivotally mounted at its center on brackets 9 on a pivot pin 10 mounted in such bracket. Both arms 12 and 13 of the press lever extend generally in the direction of the chute above both press chambers. In the present embodiment, the press lever is shaped in such mannet that in its center there is a passage formed to accommodate the feeding hopper 4, and the bifurcations opposite arms of the lever are width-wise dimensioned to essentially fill the free upper end of the chute along the whole length of both compression chambers, thereby forming the upper wall of the compression chambers. At the opposite ends of the press lever are double-acting hydraulic cylinders 14a and 14b, which thrust the respective arms of the lever to oscillate the lever about its center. The disposition of the press lever is such that both its arms or bifurcations can move in between a lower position in the corresponding press chamber (the position of arm 12 in FIG. 1) and an upper position (the position of arm 13 in FIG. 1) wherein it is essentially drawn out of the press chamber. When the press lever swings, the arm parts are I alternately pushed down into the respective press chamber. The lower surfaces of the arms or bifurcations, i.e.

the pressure surfaces, are provided with perforations 8a and are slightly curved; when each arm is at its upper position, the lower surface of such arm is essentially parallel with the bottom of the chute. The water which escapes from the bark upwardly through the holes 8a in the bottom of each of the press arms 12 and 13 runs along the upper surface of the respective press arm and escapes through the respective feed out orifice 21, from which it flows to said drain passage (not shown) in the 1 base of the press.

' in the chute in its axial direction. The side walls 2 and 3 of both chutes are provided at the feed space 5 with a longitudinal slot 16, through which guide pins 17, are fastened on the opposite sides of the piston, protrude outside of the side walls of the chute. Brackets 18 are fastened to the foundation plate 1 on both sides of the chute,

the piston rod 20 of each of the two hydraulic cylinders 19 being pivotally secured to the respective brackets. The guide pins 17 of the piston 15 are attached to the cylinders 19. The extent of movement of the hydrau ic cylinder is such as to allow the piston 15 to move through the feed space from one of the compression chambers, as shown in FIG. 1, into the other compression chamber. The piston 15 is perforated in the axial direction, as shown at 8b in FIG. 5.

At the delivery end of both chambers a vertical feed out orifice 21 is provided for the compressed bark. Such bark is to be, for instance, further fed onto a conveyor belt (not shown) installed below the bark press.

Both arms or bifurcations of the press lever 11 are at the orifices 21 of the chambers of the press chamber provided with a toothed member 22, which moves back and forth in front of the feed-out orifice, when the press lever swings.

The hydraulic cylinders of the press lever 11 and the piston 15 may be operationally synchronized to be lateron explained in detail. The apparatus may be provided with an ultra-sound device 23 applied on the side wall of the feed hopper such device 23 produces an impulse, when the feed space has been filled with bark to a certain height, which corresponds to the desired loading. The device 23 may be, for example, one made by Delevan Manufacturing Company, West Des Moines, Iowa, and sold under the trademark Sonac. Such device is described in Temporary Bulletin 4l5 1, dated June 1961, of the Delevan Manufacturing Company. The bark press functions in the following manner: Wet bark to be compressed and relieved from its water is fed through the feed hopper 4 to the feed space 5. When the feed space is filled to a preset height, and not before, the ultra-sound device 23 indicates such condition so that the control mechanism of the hydraulic cylinders 19 may then be operated to feed hydraulic oil under pressure into the correct end of the cylinders to move the piston 15 into the other compression chamber, for instance into chamber 6. The piston 5 quickly moves through the feed space 5 pushing the bark portion ahead to the press chamber 6. When it has passed the feed space 5, the piston is further proceeding at a lower speed toward its extreme position, which is shown in FIG. 1.

Part 12 of the press lever has, during the above described movement of the piston 15, remained in the lower position shown in FIG. 1 until the control mechanism for the cylinders 14a and 14h is operated to feed the hydraulic oil into the cylinder 14a and to drain it from the cylinder 14b, whereby, the press lever 11 swings into its other extreme position and the part 12 moves upwards. The described operation of the cylinders 14 preferably begins when the piston 15 has moved about A of its path. Because of this arrangement, the piston 15 pre-presses the bark portion in the press chamber 6 against the bark plug already established there until the lever arm 12 rises. This causes the piston 15 to push the pre-pressed bark portion and the bark plug towards the delivery end of the press chamber 6, whereby, it becomes so positioned as to be torn by the saw teeth 22 of the upwards moving arm part 12, and thereafter falls down on the described conveyor belt through the orifice 21. The piston 15 remains in the position into which it has been pushed. The cylinders 14, 14b are now operated to cause the levers 12, 13 to swing back. When lever part 12 is pushed into the press chamber 6, as above described, the fresh bark portion in the chamber 6, as well as the forward pushed bark plug become compressed and the piston 15 functions as a counterplate during this compression stage. When the lever 11 has reached the extreme position thereof shown in FIG. 1, the mechanism controlling the actuation of the cylinders 14 are operated to cause the lever 11 to swing again in a manner to cause the part 13 thereof to be pushed into the press chamber 7. Thereafter, the cylinders 19 are operated to cause the piston 15 to perform another feeding movement, whereby, the above described functions are repeated as regards the other press chamber 7.

As mentioned above, the ultra-sound device 23 signals when the desired quantity of bark has been fed into the feed space 5. Hence, it is assured that the piston 15 will not feed inadequate bark portions into the press chambers 6 and 7 and the degree of fitting of the press chambers 6, 7 remains essentially constant. Thus each of the bark portions becomes compressed to a like extent, causing the dry content of the compressed product to remain essentially similar.

Because of the double-acting operation of cylinders 14a and 1411, the pulling and pushing force is simultaneously fed to the press lever 11 by its hydraulic cylinders, which allows smaller cylinders to be used. This results in an advantageous oil flow regulation, for instance by directing the secondary oil discharged from the cylinder which is then pulling to the lower end of the cylinder which is then pushing.

The drawings and the above description are intended only to illustrate a preferred embodiment of the invention. As to its details, the bark press can be altered even considerably within the following claims. Although the invention has above been described in connection with the pressing of wood bark, it is obvious that the idea of the invention can also be applied to the processing of products of other types.

What I claim is:

1. A press adapted for the compression of bark and the like and for the removal of water from such material, comprising means providing a pair of generally aligned upwardly open compression chambers having confronting ends spaced from each other, said chambers having spaced opposite side walls, means providing a bark feeding chamber between the confronting ends of the compression chambers for supplying bark to the confronting, bark entering ends of the compression chambers, a bark feeding piston reciprocable from a position within the bark entering end of one compression chamber, through the bark feeding chamber, and into the bark entering end of the other compression chamber, means for reciprocating the piston, a two-armed press lever, means pivotally mounting the press lever intermediate its length so that the arms of the press lever alternately travel downwardly into their respective compression chambers through the open upper sides thereof as the press lever is oscillated about said pivotal mounting means therefor, the compression chambers and the respective arms of the press lever forming elongated chutes into which the piston thrusts a charge of bark, and means for oscillating the press lever.

2. A press according to claim 1, wherein the side walls of the compression chambers and the piston are perforated.

3. A press according to claim 1, wherein the compression chambers and the bark feeding chamber intermediate the compression chambers form a generally horizontal chute which is generally rectangular in cross section, said chute being open at its ends.

4. A press according to claim 3, wherein the means for oscillating the press lever comprises power means connected to an end of the press lever.

5. A press according to claim 3, wherein the means pivotally mounting the press lever comprises bearing means supporting the intermediate portion of the press lever above the chute and at the location of bark feeding chamber, and the two arms of the press lever have lower surfaces in the form of platens which compress the bark in the compression chambers.

6. A press according to claim 5, comprising a vertical delivery orifice adjacent the outer end of each compression chamber, and comprising a generally vertically extending saw tooth member connected to the end of each arm of the press lever to exert a sawing action upon the compressed bark in the delivery orifices upon oscillation of the press lever.

7. A press according to claim 5, wherein the walls of the chute at the bark feeding portion thereof is provided With longitudinally extending slots therethrough, comprising guide pins connected to the piston and extending outwardly through said slots, and wherein the means for reciprocating the piston comprises power means connected to the guide pins outwardly of the walls of the chute.

8. A press according to claim 5, wherein the means for oscillating the press lever and the means for reciprocating the piston both comprise power means driven by fluid under pressure.

References Cited UNITED STATES PATENTS Bessemer 100-186 X Wilkinson 100209 X Hayes 100209 Wilson 100--186 X Power 100-116 X Guettler 100-186 Englund 100-49 X Raney et a1 100--232 X Cowan et al 100-410 X BILLY J. WILHITE, Primary Examiner. 

1. A PRESS ADAPTED FOR THE COMPRESSION OF BARK AND THE LIKE AND FOR THE REMOVAL OF WATER FROM SUCH MATERIAL, COMPRISING MEANS PROVIDING A PAIR OF GENERALLY ALIGNED UPWARDLY OPEN COMPRESSION CHAMBERS HAVING CONFRONTING ENDS SPACED FROM EACH OTHER, SAID CHAMBERS HAVING SPACED OPPOSITE SIDE WALLS, MEANS PROVIDING A BARK FEEDING CHAMBER BETWEEN THE CONFRONTING ENDS OF THE COMPRESSION CHAMBERS FOR SUPPLYING BARK TO THE CONFRONTING, BARK ENTERING ENDS OF THE COMPRESSION CHAMBERS, A BARK FEEDING PISTON RECIPROCABLE FROM A POSITION WITHIN THE BARK ENTERING END OF ONE COMPRESSION CHAMBER, THROUGH THE BARK FEEDING CHAMBER, AND INTO THE BARK ENTERING END OF THE OTHER COMPRESSION CHAMBER, MEANS FOR RECIPROCATING THE PISTON, A TWO-ARMED PRESS LEVER, MEANS PIVOTALLY MOUNTING THE PRESS LEVER INTERMEDIATE ITS LENGTH SO THAT THE ARMS OF THE PRESS LEVER ALTERNATELY TRAVEL DOWNWARDLY INTO THEIR RESPECTIVE COMPRESSION CHAMBERS THROUGH THE OPEN UPPER SIDES THEREOF AS THE PRESS LEVER IS OSCILLATED ABOUT SAID PIVOTAL MOUNTING MEANS THEREFOR, THE COMPRESSION CHAMBERS AND THE RESPECTIVE ARMS OF THE PRESS LEVER FORMING ELONGATED CHUTES INTO WHICH THE PISTON THRUSTS A CHARGE OF BARK, AND MEANS FOR OSCILLATING THE PRESS LEVER. 